Liquid mixing valves which permit control of multiple flow parameters by operation of a single handle are, in general, known. The fluid mixing valve disclosed in U.S. Pat. No. 3,167,086 to Michalski (1965) includes a handle which, as a result of being movable only within a slot of an upper surface of a cover of the valve, can be moved rectilinearly (in the y-axis direction) for water temperature regulation, and # rotated for water volume regulation (or for closing or opening the valve). Since the water can only flow when a groove passage defined in a spherical valve body is aligned with an outlet passage, and since the valve body can only be displaced through a very small angle in a rotary circle, the amount of rotation available for water volume regulation is minimal. In addition, the up-and-down (y-axis) moving angle for water temperature regulation is also relatively small.
In U.S. Pat. No. 3,422,849 to Manoogian (1969) discloses a mixing valve wherein a handle stem is attached to a valve body in which is defined a recessed portion. Due to this arrangement, the water flowing through the valve must pass around a mixing groove in communication with an outlet duct before reaching the outlet duct. Consequently, the water-tight accessories (e.g., fittings) used in the disclosed device are rather complicated.